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Subject: thin filmWoS Q: Q2

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    Article
    Citation - WoS: 8
    Citation - Scopus: 8
    Study of the Structural and Optical Properties of Thallium Gallium Disulfide (tlgas2) Thin Films Grown Via Thermal Evaporation
    (Iop Publishing Ltd, 2022) Isik, M.; Karatay, A.; Ech-Chergui, A. N.; Gasanly, N. M.
    Thallium gallium disulfide (TlGaS2) belonging to layered structured semiconducting family has been a significant compound due to its outstanding characteristics. Its layered characteristics take attention for two-dimensional (2D) material research area and thus TlGaS2 is known as promising layered compound to develop 2D materials for optoelectronic devices. To the best of our knowledge, the present work is the first one investigating TlGaS2 thin films grown by thermal evaporation method. The current study focused into the structural, morphological, and optical characteristics of thermally evaporated TlGaS2 thin films. X-ray diffraction pattern of the films exhibited one peak around 36.10 degrees which was associated with (-422) plane of the monoclinic crystalline structure. The atomic compositional ratio of Tl:Ga:S was found to be suitable for the chemical formula of TlGaS2. Scanning electron microscopy images showed uniformly and narrowly deposited nanoparticles with sizes varying between 100 and 200 nm. Room temperature transmission measurements were recorded to obtain the bandgap energy of the evaporated thin films. Tauc analyses indicated direct band gap energy of 2.60 eV. Finally, Urbach energy was obtained as 95 meV. The results of the present paper would provide valuable insight to 2D material technology to understand the potential device applications of the TlGaS2.
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    Article
    Citation - WoS: 26
    Citation - Scopus: 26
    Fabrication and Some Physical Properties of Agin5s8< Thin Films
    (Elsevier Science Sa, 2004) Qasrawi, AF; Kayed, TS; Ercan, I
    AgIn5S8 thin films are deposited on glass substrates, kept at 300 K, by thermal evaporation of AgIn5S8 single crystals under the pressure of 10-5 Torr. The X-ray fluorescence analysis revealed that the films have a weight percentage of similar to11.5% Ag, 61.17% In, and 27.33% S which corresponds to 1:5:8 stoichiometric composition. X-ray analysis of the films reveals the polycrystalline nature of the films. The lattice parameter (a) of the films was calculated to be 10.784(5) Angstrom. The dark n-type electrical conductivity of the films was measured in the temperature range of 30-350 K. The conductivity data analysis shows that the thermionic emission of the charge carriers having activation energies of 147 and 224 meV in the temperature ranges of 130-230 and 240-350 K, respectively, are the dominant transport mechanism in the films. The variable range hopping transport mechanism is dominant below 130 K. The room temperature photocurrent-photon energy dependency predicts a band gap of 1.91 eV of the films. The illumination intensity-photocurrent dependency measured in the intensity range of 13-235 W cm(-2) reveals monomolecular recombination (linear) in the films and bimolecular recombination (sublinear) at the film surface corresponding to low and high applied illumination intensities, respectively. The time-dependant photocurrent measured at fixed illumination intensity reveals a response time of 0.85, 2.66 and 10.0 s in the time periods of 0-0.5, 0.5-1.0, and 1.0-10.0 s, respectively. (C) 2004 Elsevier B.V. All rights reserved.
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    Article
    Citation - WoS: 5
    Citation - Scopus: 6
    Influence of Temperature on Optical Properties of Electron-Beam Znse Thin Film
    (Iop Publishing Ltd, 2020) Gullu, H. H.; Isik, M.; Gasanly, N. M.; Parlak, M.
    Structural and optical properties of ZnSe thin films grown by electron-beam evaporation technique were reported in the present paper. X-ray diffraction pattern exhibited a single peak around 27 degrees which is well-suited with cubic phase of the films. Energy dispersive X-ray spectroscopy analyses resulted in atomic composition ratio of Zn/Se nearly 1.0 which corresponds to the chemical formula of ZnSe. Transmission experiments were performed at various temperatures in between 10 and 300 K. The analyses of the transmission data showed that direct band gap energy of the ZnSe thin films increases from 2.72 to 2.83 eV as temperature was reduced to 10 K from room temperature. The Varshni and O'Donnell-Chen models giving the temperature-band gap energy relation were used to get various optical parameters of the evaporated thin films. Analyses resulted in absolute zero temperature band gap energy as 2.83 eV, temperature coefficient as -5.8 x 10(-4) eV K-1 and average phonon energy as 16 meV. Urbach tail state energies were also calculated using absorption coefficient in the low photon energy region as increasing from 173 meV (300 K) to 181 meV (10 K) with decreasing ambient temperature.